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If A = {1, 2, 3, 4 }, define relations on A which have properties of being: symmetric but neither reflexive nor transitive

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Question

If A = {1, 2, 3, 4 }, define relations on A which have properties of being: 
symmetric but neither reflexive nor transitive

Sum
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Solution

Given that, A = {1, 2, 3}.

Let R2 = {(1, 2), (2, 1)}

Now, (1, 2) ∈ R2, (2, 1) ∈ R2

So, it is symmetric,

And, clearly R2 is not reflexive as (1, 1) ∉ R2

Also, R2 is not transitive as (1, 2) ∈ R2, (2, 1) ∈ R2 but (1, 1) ∉ R2

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Chapter 1: Relations And Functions - Exercise [Page 12]

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NCERT Exemplar Mathematics Exemplar [English] Class 12
Chapter 1 Relations And Functions
Exercise | Q 16. (b) | Page 12

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